Habitat suitability models for the conservation of thermophilic grasshoppers and bush crickets—simple or complex?

One goal of conservation biology is the assessment of effects of land use change on species distribution. One approach for identifying the factors, which determine habitat suitability for a species are statistical habitat distribution models. These models are quantitative and can be used for predictions in management scenarios. However, they often have one major shortcoming, which is their complexity. This means that they need several, often costly-to-determine parameters for predictions of species occurrence. We first used habitat suitability models to investigate and determine habitat preferences of three different Orthoptera species. Second, we compared the predictive powers of simple habitat suitability models considering only the ‘habitat type' as predictor with more complex models taking different habitat factors into account. We found that the habitat type is the most reliable and robust factor, which determines the occurrence of the species studied. Thus, analyses of habitat suitability can easily be carried out on the basis of existing vegetation maps for the conservation of the three species under study. Our results can serve as a basis for the estimation of spatio-temporal distribution and survival probabilities of the species studied and might also be valuable for other species living in dry grassland

Is cell segregation like oil and water: asymptotic versus transitory regime

Segregation of different cell types is a crucial process for the pattern formation in tissues, in particular during embryogenesis. Since the involved cell interactions are complex and difficult to measure individually in experiments, mathematical modelling plays an increasingly important role to unravel the mechanisms governing segregation. The analysis of these theoretical models focuses mainly on the asymptotic behavior at large times, in a steady regime and for large numbers of cells. Most famously, cell-segregation models based on the minimization of the total surface energy, a mechanism also driving the demixing of immiscible fluids, are known to exhibit asymptotically a particular algebraic scaling behavior. However, it is not clear, whether the asymptotic regime of the numerical models is relevant at the spatio-temporal scales of actual biological processes and in-vitro experiments. By developing a mapping between cell-based models and experimental settings, we are able to directly compare previous experimental data to numerical simulations of cell segregation quantitatively. We demonstrate that the experiments are reproduced by the transitory regime of the models rather than the asymptotic one. Our work puts a new perspective on previous model-driven conclusions on cell segregation mechanisms.Comment: 24 pages, 7+4 figure

disrupted relationship with memory performance and potential implications for delusions

Recent concepts have highlighted the role of the hippocampus and adjacent medial temporal lobe (MTL) in positive symptoms like delusions in schizophrenia. In healthy individuals, the MTL is critically involved in the detection and encoding of novel information. Here, we aimed to investigate whether dysfunctional novelty processing by the MTL might constitute a potential neural mechanism contributing to the pathophysiology of delusions, using functional magnetic resonance imaging (fMRI) in 16 unmedicated patients with paranoid schizophrenia and 20 age-matched healthy controls. All patients experienced positive symptoms at time of participation. Participants performed a visual target detection task with complex scene stimuli in which novel and familiar rare stimuli were presented randomly intermixed with a standard and a target picture. Presentation of novel relative to familiar images was associated with hippocampal activation in both patients and healthy controls, but only healthy controls showed a positive relationship between novelty- related hippocampal activation and recognition memory performance after 24 h. Patients, but not controls, showed a robust neural response in the orbitofrontal cortex (OFC) during presentation of novel stimuli. Functional connectivity analysis in the patients further revealed a novelty-related increase of functional connectivity of both the hippocampus and the OFC with the rostral anterior cingulate cortex (rACC) and the ventral striatum (VS). Notably, delusions correlated positively with the difference of the functional connectivity of the hippocampus vs. the OFC with the rACC. Taken together, our results suggest that alterations of fronto-limbic novelty processing may contribute to the pathophysiology of delusions in patients with acute psychosis

Safe birth matters: facilitators and barriers to uptake of the WHO safe childbirth checklist tool in a Tanzania Regional Hospital

Background: The World Health Organization (WHO) developed the Safe Birth Checklist (SCC) to facilitate best practices in safe birthing practices. The SCC is utilizing existing evidence-based WHO guidelines and recommendations which has combined those into a single and practical bedside tool. The SCC is the first checklist-based intervention to target the prevention of maternal and neonatal deaths. Objective: The objective of this project was to pilot-test the World Health Organization Safe Childbirth Checklist with Maternity Regional Hospital in, Tanzania. Study Design and Methods: Retrospective analysis on 35 charts were completed to identify presence or absence of documentation aligned with evidenced based checklist items. Staff training, end user observations and focus group discussions were utilized to elicit feedback about the tool and the process. Descriptive statistics and manual content analysis were used to analyze the rate of uptake and ownership over the checklist. The Checklist is broken down into four sections or time points (that are considered natural pause points in the care of laboring women). The four different pause points are admission, delivery, post-partum, and discharge Results: We trained 26 participants out of 32 staff how to use the SCC. Delivery time point had the lowest at SCC completion rate at 39% compared to discharge having the highest completion rate at 93%. There was variation in completion rate of the checklist items at each time point. Checklist items at the beginning of each time point were completed between 94% and 100% of the time with the latter checklist list items completed between 29% and 57% of the time Conclusion: This project was able to identify facilitators and potential barriers to the successful uptake of the Safe Childbirth Checklist in Shinyanga Regional Hospital. Based on these findings, the MOH have opportunities to utilize those findings in the scale-up of the implementation of the checklist and future evaluation activities

Breeding birds survey in agrarian landscapes of Brandenburg – between species richness and poverty

For the assessment of biodiversity in agrarian landscapes (here in case of breeding birds) an effective, random sampling based monitoring approach was developed. It was practically tested in the federal state of Brandenburg in the years 2005 and 2006. The number of species at 1 km2 observation sites ranged between 5 and 41 (mean 22.2) and the number of reveres ranged between 21 and 217 (mean 80.3) in the whole Brandenburg above both the years. The enormous variation shows a high potential of species diversity and population abundance on the one hand and extreme poverty on the other hand. The species inventory demonstrates a narrow relation to landscape structure. Methodical experience of this special bird monitoring approach can be also used for creating new survey approaches considering other ecological variables in order to verify the effect of agri-environmental measures as well as to develop new agri-environment programmes at field and landscape level. The approach has proved its usefulness concerning ecological results as well as technical and organizional flexibility.Für die Ermittlung der Biodiversität in Agrarlandschaften (hier am Beispiel der Brutvögel) wurde ein auf stichprobentheoretischer Grundlage basierendes, geschichtetes, großräumiges Monitoring entwickelt und in den Jahren 2005 und 2006 flächendeckend in Brandenburg erprobt. Die Artenzahlen auf den 1 km2 Beobachtungsflächen schwankten zwischen 5 und 41 (Mittelwert 22,2) und die Zahl der ermittelten Brutvogelreviere/ km2 lag zwischen 21 und 217 (Mittelwert 80,3) im gesamten Bundesland Brandenburg über beide Jahre. Diese enorme Streubreite verweist einerseits auf ein hohes Artendiversitäts- bzw. ein hohes Abundanzpotenzial in den Agrarlandschaften und andererseits auf eine große Armut bestimmter Flächen. Die Artenausstattung zeigt eine hohe Bindung an die Landschaftsstrukturen. Die methodischen Erkenntnisse aus dem Brutvogelmonitoring weisen neue Wege zur langfristigen Erfolgskontrolle von Agrar-Umwelt- Maßnahmen und zur Ableitung von effizienten, zielorientierten Agrar-Umwelt-Maßnahmen auf den Produktionsflächen und im Landschaftsmaßstab. Der Monitoring-Ansatz hat sich sowohl hinsichtlich der ökologischen Ergebnisse als auch hinsichtlich der technisch-organisatorischen Durchführbarkeit bewährt

New Perspectives on Nitrogen Fixation Measurements Using 15N2 Gas

Recently, the method widely used to determine 15N2 fixation rates in marine and freshwater environments was found to underestimate rates because the dissolution of the added 15N2 gas bubble in seawater takes longer than theoretically calculated. As a solution to the potential underestimate of rate measurements, the usage of the enriched water method was proposed to provide constant 15N2 enrichment. Still, the superiority of enriched water method over the previously used bubble injection remains inconclusive. To clarify this issue, we performed laboratory based experiments and implemented the results into an error analysis of 15N2 fixation rates. Moreover, we conducted a literature search on the comparison of the two methods to calculate a mean effect size using a meta-analysis approach. Our results indicate that the error potentially introduced by an equilibrium phase of the 15N2 gas is −72% at maximum for experiments with very short incubation times of 1 h. In contrast, the underestimation was negligible for incubations lasting 12–24 h (error is −0.2%). Our meta-analysis indicates that 84% of the measurements in the two groups will overlap and there is a 61% chance that a sample picked at random from the enriched water group will have a higher value than one picked at random from the bubble group. Overall, the underestimation of N2 fixation rates when using the bubble method relative to the enriched water method is highly dependent on incubation time and other experimental conditions and cannot be generalized

New Perspectives on Nitrogen Fixation Measurements Using ¹⁵N₂ Gas

International audienc

Oscillating magnetic field disrupts magnetic orientation in Zebra finches, Taeniopygia guttata

Background Zebra finches can be trained to use the geomagnetic field as a directional cue for short distance orientation. The physical mechanisms underlying the primary processes of magnetoreception are, however, largely unknown. Two hypotheses of how birds perceive magnetic information are mainly discussed, one dealing with modulation of radical pair processes in retinal structures, the other assuming that iron deposits in the upper beak of the birds are involved. Oscillating magnetic fields in the MHz range disturb radical pair mechanisms but do not affect magnetic particles. Thus, application of such oscillating fields in behavioral experiments can be used as a diagnostic tool to decide between the two alternatives. Methods In a setup that eliminates all directional cues except the geomagnetic field zebra finches were trained to search for food in the magnetic north/south axis. The birds were then tested for orientation performance in two magnetic conditions. In condition 1 the horizontal component of the geomagnetic field was shifted by 90 degrees using a helmholtz coil. In condition 2 a high frequently oscillating field (1.156 MHz) was applied in addition to the shifted field. Another group of birds was trained to solve the orientation task, but with visual landmarks as directional cue. The birds were then tested for their orientation performance in the same magnetic conditions as applied for the first experiment. Results The zebra finches could be trained successfully to orient in the geomagnetic field for food search in the north/south axis. They were also well oriented in test condition 1, with the magnetic field shifted horizontally by 90 degrees. In contrast, when the oscillating field was added the directional choices during food search were randomly distributed. Birds that were trained to visually guided orientation showed no difference of orientation performance in the two magnetic conditions

Educating Future Nursing Scientists: Recommendations for Integrating Omics Content in PhD Programs

Preparing the next generation of nursing scientists to conduct high-impact, competitive, sustainable, innovative, and interdisciplinary programs of research requires that the curricula for PhD programs keep pace with emerging areas of knowledge and health care/biomedical science. A field of inquiry that holds great potential to influence our understanding of the underlying biology and mechanisms of health and disease is omics. For the purpose of this article, omics refers to genomics, transcriptomics, proteomics, epigenomics, exposomics, microbiomics, and metabolomics. Traditionally, most PhD programs in schools of nursing do not incorporate this content into their core curricula. As part of the Council for the Advancement of Nursing Science\u27s Idea Festival for Nursing Science Education, a work group charged with addressing omics preparation for the next generation of nursing scientists was convened. The purpose of this article is to describe key findings and recommendations from the work group that unanimously and enthusiastically support the incorporation of omics content into the curricula of PhD programs in nursing. The work group also calls to action faculty in schools of nursing to develop strategies to enable students needing immersion in omics science and methods to execute their research goals